CN111592386A - Preparation method of chelated rare earth - Google Patents
Preparation method of chelated rare earth Download PDFInfo
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- CN111592386A CN111592386A CN202010523662.2A CN202010523662A CN111592386A CN 111592386 A CN111592386 A CN 111592386A CN 202010523662 A CN202010523662 A CN 202010523662A CN 111592386 A CN111592386 A CN 111592386A
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05D—INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE
- C05D9/00—Other inorganic fertilisers
- C05D9/02—Other inorganic fertilisers containing trace elements
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G5/00—Fertilisers characterised by their form
- C05G5/20—Liquid fertilisers
- C05G5/23—Solutions
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- Organic Chemistry (AREA)
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- Pest Control & Pesticides (AREA)
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Abstract
The invention discloses a preparation method of chelated rare earth, which mainly comprises the following steps: adding a certain amount of water into a reaction kettle, adding a chelating agent EDTA into the reaction kettle according to the proportion, heating, adding sodium hydroxide, stirring for dissolving, adding a certain amount of rare earth after clearing, then adding polyphosphate, adding water to a scale by adopting a double-chelating process, and stirring for 3-4 hours; stirring, standing for 1-1.5 days, clarifying, removing impurities, placing into a finished product tank, and packaging as required; the product solves the problems of poor mixing performance with humic acid, amino acid, monopotassium phosphate, trace element water-soluble fertilizer, flush fertilizer, drip irrigation fertilizer, organic fertilizer and the like, low fertilizer utilization rate and the like.
Description
Technical Field
The invention belongs to the technical field of agriculture and chemistry, and particularly relates to a preparation method of chelated rare earth.
Background
Rare earth agriculture is an original agricultural yield increasing way in China, a few agriculturists and biologists have explored research on the problem of promoting crop growth by rare earth elements abroad before the seventies of the century, but the rare earth elements are extremely expensive at that time, so that researchers do not make systematic sudden wavelength change on the rare earth agriculture. China carries out a large amount of systematic research work on rare earth agricultural problems from the beginning of the seventies, and the national science commission commissions the general companies of nonferrous metal industry, the agricultural department, the health department and related experts in China to comprehensively check and accept the scientific research achievements of agricultural rare earth in 1 month in 1986.
The rare earth has the main effects of promoting the rooting and the germination of crops, increasing the chlorophyll content, improving the photosynthesis efficiency of the crops, promoting the absorption and the operation of the crops on nutrient elements such as nitrogen, phosphorus and potassium and the like, increasing the yield of the crops and improving the quality of the crops in the growth process of the crops. At present, the rare earth is mainly applied to apple, pear, banana, vegetable, facility agriculture, peanut, forest, flower and seedling and other economic crops, and the yield can be increased by about 12 percent by using the rare earth alone.
The rare earth has better effects on preventing freezing and early germination of crops, protecting flowers and fruits, improving sugar degree, coloring and brightening, ensuring a round fruit shape, maturing in advance, reducing the natural fragrance of fruits and vegetables and the like, but has poor mixing performance with humic acid, amino acid, monopotassium phosphate, trace element water-soluble fertilizer, flush fertilizer, drip irrigation fertilizer, organic fertilizer, compound (mixed) fertilizer, insecticide and bactericide and herbicide, and is labor-consuming and time-consuming when being singly sprayed, and the effect of the rare earth on the crops cannot be fully exerted.
Disclosure of Invention
The invention aims to provide a preparation method of chelated rare earth, which solves the problems of poor mixing performance with humic acid, amino acid, monopotassium phosphate, trace element water-soluble fertilizer, flush fertilizer, drip irrigation fertilizer, organic fertilizer, compound (mixed) fertilizer, insecticide, bactericide, herbicide and the like, low fertilizer utilization rate and the like.
The invention provides a preparation method of chelated rare earth, which comprises the following steps:
s1, under stirring, firstly adding a certain amount of water into a reaction kettle, then adding the chelating agent EDTA into the reaction kettle according to the proportional amount, and completely dissolving the chelating agent EDTA into the water by means of mechanical stirring and auxiliary heating to form a solution a; wherein the mass ratio of the chelating agent EDTA to the water is 1 (4-5), and the temperature of the liquid in the reaction kettle is 65-85 ℃;
s2, adding sodium hydroxide into the solution a under stirring, continuously stirring and dissolving in a mechanical stirring and auxiliary heating mode until the liquid in the reaction kettle is clear and transparent and has no suspended matters to obtain a solution b; the mass ratio of the sodium hydroxide to the chelating agent EDTA is 1 (2.5-4); the temperature of the liquid in the reaction kettle is 65-85 ℃;
s3, under stirring, sequentially adding a certain amount of rare earth nitrate and polyphosphate into the solution b, then adjusting to the standard scale of a reaction kettle by using water, continuously stirring for 3-4 hours in a mechanical stirring and auxiliary heating mode, wherein the temperature of liquid in the reaction kettle is 65-85 ℃, standing for 1-1.5 days after the reaction is stopped, and stopping stirring and heating in the standing process; the mass ratio of the rare earth nitrate to the chelating agent EDTA is (3-5) to 1, and the mass ratio of the polyphosphate to the chelating agent EDTA is (5-6) to 1;
and S4, opening a valve at the bottom of the reaction kettle, removing impurities generated after standing in the step S3, and then metering and subpackaging clear liquid.
According to the preparation method of the chelated rare earth, in the step S1, the mass ratio of the chelating agent EDTA to the water is 1:5, and the temperature of the liquid in the reaction kettle is 80 ℃;
the method of claim, wherein the mass ratio of sodium hydroxide to EDTA in step S2 is 1: 3.
In the above method for preparing chelated rare earth, the rare earth nitrate in step S3 is 38% rare earth nitrate powder.
In the above method for preparing chelated rare earth, in step S3, the mass ratio of rare earth nitrate to chelating agent EDTA is 4:1, and the mass ratio of polyphosphate to chelating agent EDTA is 5: 1.
The invention discloses a preparation method of chelated rare earth, which mainly has the following technical advantages:
1. the compound rare earth additive can be used as an additive raw material, and has the effect of 3-5 times that of common rare earth.
2. The invention effectively solves the problem of poor mixing of rare earth, humic acid, amino acid, trace element water soluble fertilizer, flush fertilizer, drip irrigation fertilizer, organic fertilizer, compound fertilizer, pesticide, bactericide and herbicide, and has obvious effect after being added, thereby improving the utilization rate of the fertilizer, saving labor, time and money and conforming to the principle of chemical fertilizer reduction and synergism advocated by the state.
Detailed Description
To better illustrate the preparation and use of the disclosed chelated rare earths, the invention is further illustrated in the following examples. The specific embodiments are merely illustrative of the present invention and do not limit the present invention.
Example 1:
the invention provides a preparation method of chelated rare earth, which comprises the following steps:
s1, under stirring, firstly adding a certain amount of water into a reaction kettle, then adding the chelating agent EDTA into the reaction kettle according to the proportional amount, and completely dissolving the chelating agent EDTA into the water by means of mechanical stirring and auxiliary heating to form a solution a; wherein the mass ratio of the chelating agent EDTA to the water is 1:5, and the temperature of the liquid in the reaction kettle is 80 ℃;
s2, adding sodium hydroxide into the solution a under stirring, continuously stirring and dissolving in a mechanical stirring and auxiliary heating mode until the liquid in the reaction kettle is clear and transparent and has no suspended matters to obtain a solution b; the mass ratio of the sodium hydroxide to the chelating agent EDTA is 1: 4; the temperature of the liquid in the reaction kettle is 80 ℃;
s3, under stirring, sequentially adding a certain amount of rare earth nitrate and polyphosphate into the solution b, then adjusting to the standard scale of a reaction kettle by using water, continuously stirring for 3 hours in a mechanical stirring and auxiliary heating mode, wherein the temperature of liquid in the reaction kettle is 80 ℃, standing for 1 day after the reaction is stopped, and stopping stirring and heating in the standing process; the mass ratio of the rare earth nitrate to the chelating agent EDTA is 4:1, and the mass ratio of the polyphosphate to the chelating agent EDTA is 5: 1;
and S4, opening a valve at the bottom of the reaction kettle, removing impurities generated after standing in the step S3, and then metering and subpackaging clear liquid.
Through research, the chelated rare earth and the common rare earth are different from each other in that: and (3) taking a little of the chelating rare earth stock solution, and dripping a few drops of ethephon into the chelating rare earth stock solution to form white gelatinous colloid immediately.
The chelating of rare earth has obvious advantages:
1. the compound fertilizer has good mixing property, can be mixed with an insecticide, a bactericide and a foliar fertilizer, and overcomes the defect that common rare earth cannot be mixed with foliar fertilizer monopotassium phosphate and a bactericide containing mancozeb;
2. is favorable for reducing the quantity and improving the efficiency of the fertilizer, combines the rare earth and the chelating agent into organic rare earth, is favorable for crops to absorb and utilize, improves the utilization rate of the fertilizer by 30 percent, can save 20 to 30 percent of the fertilizer, and conforms to the national principle of reducing the quantity and improving the efficiency of the fertilizer
3. The chelating agent is green and environment-friendly, is easy to degrade, is safe without residue, is rich in organic phosphorus, can be directly degraded into orthophosphate ions, and provides necessary phosphorus elements for the growth and development of crops.
4. The chelated rare earth can reduce the content of heavy metals such as lead, cadmium and arsenic in crops; the chelated rare earth has high electrovalence and high charge density, and can compete with heavy metal for complexing sites to discharge the heavy metal out of crops.
5. The effect is good, the chelated rare earth is in an organic ionic state, the effect is 3-5 times of that of common rare earth, the more sufficient the crop nutrition is, the better the chelated rare earth effect is, and the characteristic of 'strong and stronger the chelated rare earth' is incomparable with other fertilizers.
6. The chelated rare earth has obvious effect of improving the quality of crops, and the crops can be sold at a good price after being high in quality. From the perspective of consumer awareness of farmers, especially farmers in economic crops and vegetable planting areas, are aware of the development space of organic food and green food, so that the market prospect of chelating rare earth is wider and wider.
7. The chelated rare earth can replace the functions of hormones such as compound sodium nitrophenolate, swelling element, DA-6 and the like, and the vigorous development of the chelated rare earth has strategic significance on the premise that the current country completely forbids the use of the hormones added into the fertilizer.
The development of chelated rare earth changes the traditional agricultural fertilization structure, brings deep influence and change to the agricultural field and human life, and is a hot spot for many fertilizer enterprises in the future.
The rare earth elements have obvious improvement effect on the growth, development, yield and quality of crops, although the physiological action mechanism of the rare earth elements in plants is not very clear, the rare earth elements have been proved by the prior experiments that: the rare earth can promote the operation and absorption of nutrient elements N, P, K, S, B, Mo, the plant can form amino acid and protein only after absorbing nitrate nitrogen from the growing environment and reducing the nitrate nitrogen into ammonia nitrogen, and the content of ammonium nitrogen in the leaves is greatly increased under the catalytic action of enzyme after the plant leaves are sprayed with the rare earth. Meanwhile, the rare earth can increase the control of the cell membrane on the electrolyte seepage and improve the drought and cold resistance of the plant, namely the capability of resisting the adverse circumstances.
The chelated rare earth is suitable for single spraying, flushing application, drip irrigation, sprinkling and the like, and can also be used as an additive raw material for producing amino acid, humic acid, monopotassium phosphate, trace elements, flushing fertilizer, drip irrigation fertilizer and compound (mixed) fertilizer, and the effect is multiplied after the addition. The blending method is simple, easy to industrialize, remarkable in effect, stable and high in economic benefit, meets six development trends of high efficiency, compounding, long-acting, diversification, functionalization and low carbon of a novel fertilizer, solves the problems of low fertilizer utilization rate, reduced agricultural product quality, environmental pollution, excessive heavy metal, fertilizer damage and the like, improves the natural fragrance of fruits and vegetables, colors brightly, colors round fruits, improves the sugar degree, protects flowers and fruits, prevents cracking and rust removal, improves the anti-stress capabilities of drought resistance, cold resistance, continuous cropping resistance and the like, and has great popularization and application values.
The application method of the product of the invention comprises the following steps:
the addition amount of the large chemical fertilizer and the compound fertilizer is three to five per thousand per ton;
the addition amount of the water flush fertilizer and the drip irrigation fertilizer per ton is 4-5%;
the addition amount of the foliar fertilizer is 8-10% per ton;
is sprayed by 3000 times of 2000-fold.
The test proves that: the product of the invention has the yield increasing effect obviously higher than that of common rare earth, and the rare earth element and the phosphorus element have obvious synergistic action. Moreover, the thousand seed weight and the hundred fruit weight of the crops applied with the chelated rare earth are obviously increased, which shows that the fruit plump degree is increased, the vitamin C content of the apples is increased by about several times, and the total sugar content is obviously increased (see table 2).
Table 1 comparison of the effects of example 1 and ordinary rare earth on yield increase (mean of repetition) (%)
Note: the land strength of the test field is consistent
Table 2 example 1 increase in the effect on fruit quality (%), compared to conventional rare earths (%)
The chelating rare earth can increase the crop yield by 12-35%, the input-output ratio is 1:30, and the use of the chelating rare earth for crops can obtain great economic and social benefits.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention, and it is to be understood that the present invention is not limited thereto, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are included in the scope of the present invention.
Claims (5)
1. The preparation method of the chelated rare earth is characterized by comprising the following steps:
s1, under stirring, firstly adding a certain amount of water into a reaction kettle, then adding the chelating agent EDTA into the reaction kettle according to the proportional amount, and completely dissolving the chelating agent EDTA into the water by means of mechanical stirring and auxiliary heating to form a solution a; wherein the mass ratio of the chelating agent EDTA to the water is 1 (4-5), and the temperature of the liquid in the reaction kettle is 65-85 ℃;
s2, adding sodium hydroxide into the solution a under stirring, continuously stirring and dissolving in a mechanical stirring and auxiliary heating mode until the liquid in the reaction kettle is clear and transparent and has no suspended matters to obtain a solution b; the mass ratio of the sodium hydroxide to the chelating agent EDTA is 1 (2.5-4); the temperature of the liquid in the reaction kettle is 65-85 ℃;
s3, under stirring, sequentially adding a certain amount of rare earth nitrate and polyphosphate into the solution b, then adjusting to the standard scale of a reaction kettle by using water, continuously stirring for 3-4 hours in a mechanical stirring and auxiliary heating mode, wherein the temperature of liquid in the reaction kettle is 65-85 ℃, standing for 1-1.5 days after the reaction is stopped, and stopping stirring and heating in the standing process; the mass ratio of the rare earth nitrate to the chelating agent EDTA is (3-5) to 1, and the mass ratio of the polyphosphate to the chelating agent EDTA is (5-6) to 1;
and S4, opening a valve at the bottom of the reaction kettle, removing impurities generated after standing in the step S3, and then metering and subpackaging clear liquid.
2. The method of claim 1, wherein the chelating agent is selected from the group consisting of: in the step S1, the mass ratio of the chelating agent EDTA to the water is 1:5, and the temperature of the liquid in the reaction kettle is 80 ℃.
3. The method of claim 1, wherein the chelating agent is selected from the group consisting of: the mass ratio of the sodium hydroxide to the chelating agent EDTA in the step S2 is 1: 3.
4. The method of claim 1, wherein the chelating agent is selected from the group consisting of: in the step S3, the rare earth nitrate is 38% rare earth nitrate powder.
5. The method of claim 1, wherein the chelating agent is selected from the group consisting of: in the step S3, the mass ratio of the rare earth nitrate to the chelating agent EDTA is 4:1, and the mass ratio of the polyphosphate to the chelating agent EDTA is 5: 1.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115417721A (en) * | 2022-09-16 | 2022-12-02 | 南昌常茂新材料有限公司 | Preparation method of high-purity chelated rare earth fertilizer |
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2020
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115417721A (en) * | 2022-09-16 | 2022-12-02 | 南昌常茂新材料有限公司 | Preparation method of high-purity chelated rare earth fertilizer |
| CN115417721B (en) * | 2022-09-16 | 2024-04-19 | 南昌常茂新材料有限公司 | Preparation method of high-purity chelated rare earth fertilizer |
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